Does in vitro hemolysis affect measurements of plasma apixaban concentration by UPLC-MS and anti-Xa assay?

INTRODUCTION: Hemolytic interference may impact various laboratory tests, including coagulation analyses. Apixaban is the most commonly used direct oral anticoagulant in Norway, and there is lacking knowledge on how apixaban concentration measurements might be influenced by hemolysis. Moreover, hemolysis-induced alterations in apixaban levels could potentially impact the risk of bleeding in specific clinical scenarios. We wanted to study whether hemolysis would increase apixaban concentration and investigate the impact of hemolytic interference on apixaban concentration measurements. METHODS: Blood samples from 20 apixaban-treated patients and 8 healthy controls were hemolyzed in vitro by a freeze method. The degree of hemolysis was measured with plasma free hemoglobin (PfHb) at baseline and two levels of hemolysis. Apixaban concentration was measured in plasma using both the chromogenic anti-Xa method and the ultraperformance liquid chromatography mass spectrometry (UPLC-MS). Thrombin generation assay was performed to assess coagulability. RESULTS: UPLC-MS measurements showed a mean concentration change of -1.66% (±3.2%, p = 0.005) and anti-Xa assay showed a mean concentration change of 3.37% (±6.5%, p = 0.09) with increasing hemolysis. Thrombin generation lagtime decreased, and endogenous thrombin potential and peak thrombin increased with increasing hemolysis in both the control group and the apixaban group. CONCLUSION: Apixaban concentration measurements by anti-Xa assay and UPLC-MS were not affected by hemolysis to a clinically relevant extent. Furthermore, hemolysis did not lead to hypocoagulability when assessed by thrombin generation.

Trends in the prevalence of breastfeeding up to 6 months of age using structured data from routine child healthcare visits.

AIM: The Norwegian Action Plan for a Healthier Diet (2017-2021) set the target that 25% of infants should be exclusively breastfed for 6 months by 2022. Our aim was to determine trends in the prevalence and duration of breastfeeding in the municipality of Bergen. METHODS: Data on breastfeeding status in 2010-2018 were extracted from a standardised electronic medical record kept by public child health centres and recorded as exclusive, partial or none, at 6 weeks and 6 months of age. RESULTS: We found that 28,503 and 26,735 infants attended the 6-week and 6-month consultations, respectively. The prevalence of any breastfeeding was 92.0% at 6 weeks and 78.0% at 6 months with no trend over time between 2010 and 2018. The prevalence of exclusive breastfeeding at 6 weeks was 73.9% and stable over time, but it declined at 6 months, from 28.1% in 2010 to 11.1% in 2014 and remained stable thereafter. CONCLUSION: During 2010-2018, the prevalence of any and exclusive breastfeeding at 6 weeks and any breastfeeding at 6 months was stable. Exclusive breastfeeding at 6 months declined halfway through the study period, to a stable, but low, prevalence of 11.1% by 2014.

Development of Social and Demographic Differences in Maternal Smoking Between 1999 and 2014 in Norway.

INTRODUCTION: The Medical Birth Registry of Norway provides national coverage of all births in Norway. In this study trends of smoking at the beginning of pregnancy and the variation of these trends across different sociodemographic groups are analyzed. This knowledge is important for planning interventions both in the general population and specifically among pregnant women. METHODS: All births registered in Medical Birth Registry of Norway 1999-2014 with information on mothers' smoking status were included in the overall analyses of the smoking trends (806 298). Records from 210 268 births in two time periods 1999-2000 and 2013-2014 were selected, and for the multivariate analyses we used general linear models to provide adjusted risk ratios. RESULTS: The prevalence of maternal smoking at the beginning of pregnancy decreased from 25% to 8% over the 15-year period. Mothers with low, medium, and high education, respectively, had a 46% (RR 0.54, CI 0.52-0.55), 62% (RR 0.38, CI 0.37-0.40), and 80% (RR 0.20, CI 0.19-0.22) reduction in maternal smoking between the two time periods. Similarly, the decline in smoking was greater for mothers who were married or living together (64%; RR 0.36, CI 0.35-0.37) than for single mothers (39%; RR 0.61, CI 0.58-0.64). Immigrants had a lower smoking prevalence than Norwegians in the entire period 1999-2014. CONCLUSION: The prevalence of smoking during pregnancy in Norway decreased in all population groups, but the relative differences between the educational groups increased from 1999-2000 to 2013-2014. This is a public health concern and a strong contributor to health disparities. IMPLICATIONS: Women with low and medium education level and single mothers had the highest smoking prevalence and the lowest decline over the two time periods. These groups constitute 45% of our study population, the relatively high maternal smoking in these groups continues to be of public health concern for maternal and child health.

Educational inequalities in mortality of patients with atrial fibrillation in Norway.

OBJECTIVES: We explored the educational gradient in mortality in atrial fibrillation (AF) patients. DESIGN: We prospectively followed patients hospitalized with AF as primary discharge diagnosis in the Cardiovascular Disease in Norway 2008-2012 project. The average length of follow-up was 2.4 years. Mortality by educational level was assessed by Cox proportional hazard models. Population attributable fractions (PAF) were calculated. Analyses stratified by age (≤75 and >75 years of age), and adjusted for age, gender, medical intervention, and Charlson Comorbidity Index. RESULTS: Of 42,138 AF patients, 16% died by end of 2012. Among younger patients, those with low education (≤10 years) had a HR of 2.3 (95% confidence interval 2.0, 2.6) for all-cause mortality relative to those with any college or university education. Similar results were observed for cardiovascular mortality. Disparities in mortality were greater among younger than older patients. A PAF of 35.9% (95% confidence interval 27.9, 43.1) was observed for an educational level of high school/vocational school or less versus higher education in younger patients. CONCLUSIONS: Increasing educational level associated with better prognosis suggesting underlying education-related behavioral and medical determinants of mortality. A considerable proportion of mortality within 5 years following hospital discharge could be prevented.

Implementing medical abortion with mifepristone and misoprostol in Norway 1998-2013.

Background: Medical abortion with mifepristone and misoprostol was introduced in Norway in 1998, and since then there has been an almost complete change from predominantly surgical to medical abortions. We aimed to describe the medical abortion implementation process, and to compare characteristics of women obtaining medical and surgical abortion. Methods: Information from all departments of obstetrics and gynaecology in Norway on the time of implementation of medical abortion and abortion procedures in use up to 12 weeks of gestation was assessed by surveys in 2008 and 2012. We also analysed data from the National Abortion Registry comprising 223 692 women requesting abortion up to 12 weeks of gestation during 1998-2013. Results: In 2012, all hospitals offered medical abortion, 84.4% offered medical abortion at 9-12 weeks of gestation and 92.1% offered home administration of misoprostol. The use of medical abortion increased from 5.9% of all abortions in 1998 to 82.1% in 2013. Compared with women having a surgical abortion, women obtaining medical abortion had higher odds for undergoing an abortion at 4-6 weeks (adjusted OR 2.33; 95% confidence interval 2.28-2.38). Waiting time between registered request for an abortion until termination was reduced from 11.3 days in 1998 to 7.3 days in 2013. Conclusions: Norwegian women have gained access to more treatment modalities and simplified protocols for medical abortion. At the same time they obtained abortions at an earlier gestational age and the waiting time has been reduced.